Best way to handle exceptions globally in Spring Boot REST API?

Question

I want to handle all exceptions in one place in my Spring Boot application instead of using try-catch in every controller method.

What's the best practice for global exception handling that returns proper JSON error responses?

I want to handle:
- Validation errors
- Resource not found
- Database errors
- Custom business exceptions

spring_guru · Accepted Answer

Use @ControllerAdvice for global exception handling. Here's a complete solution:

**Custom Exceptions:**
```java
public class ResourceNotFoundException extends RuntimeException {
    public ResourceNotFoundException(String message) {
        super(message);
    }
}

public class BusinessException extends RuntimeException {
    public BusinessException(String message) {
        super(message);
    }
}
```

**Global Exception Handler:**
```java
@RestControllerAdvice
@Slf4j
public class GlobalExceptionHandler {

// Handle custom not found exception
    @ExceptionHandler(ResourceNotFoundException.class)
    public ResponseEntity handleResourceNotFound(ResourceNotFoundException ex) {
        ErrorResponse error = new ErrorResponse(
            HttpStatus.NOT_FOUND.value(),
            ex.getMessage(),
            LocalDateTime.now()
        );
        return ResponseEntity.status(HttpStatus.NOT_FOUND).body(error);
    }

// Handle validation errors
    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ResponseEntity handleValidationErrors(
            MethodArgumentNotValidException ex) {

Map errors = ex.getBindingResult()
            .getFieldErrors()
            .stream()
            .collect(Collectors.toMap(
                FieldError::getField,
                FieldError::getDefaultMessage
            ));

Map response = new HashMap();
        response.put("status", HttpStatus.BAD_REQUEST.value());
        response.put("errors", errors);
        response.put("timestamp", LocalDateTime.now());

return ResponseEntity.badRequest().body(response);
    }

// Handle all other exceptions
    @ExceptionHandler(Exception.class)
    public ResponseEntity handleGlobalException(Exception ex) {
        log.error("Unexpected error: ", ex);

ErrorResponse error = new ErrorResponse(
            HttpStatus.INTERNAL_SERVER_ERROR.value(),
            "An unexpected error occurred",
            LocalDateTime.now()
        );
        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(error);
    }
}

**Error Response DTO:**
```java
@Data
@AllArgsConstructor
public class ErrorResponse {
    private int status;
    private String message;
    private LocalDateTime timestamp;
}
```

1 Answer